Propeller mounting for aeroplanes and the like



S. S. VARKAS July 7, 1931..

PROPELLER MOUNTING FOR AEROPLANES AND THE LIKE Filed Oct. 28, 1929 2 Sheets-Sheet l IN V EN TOR.

ATTORNEY July 7, 1931. 5 VARKAS 1,812,910

PROPELLER MOUNTING FOR AEROPLANES AND THE LIKE Filed Oct. 28, 1929 2 Sheets-Sheet 2 5 [f 43 68% 4/ 4a 56 69 41 a5 53 a;

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ATTORNEY Patented July 7, 1931 srmos s. vAnKAs. or NEW YORK, N. Y.

PROPELLER MOUNTING FOR AEROPLANES AND THE LIKE Application fiIed October 28, 1929. Serial No. 402,886.

This invention relates to new and useful improvements in propeller mountings for aeroplanes and the like.

The invention has foran object the provision of a device of the class mentioned which is of simple durable construction, dependable in use and efiicient in action, and which can be manufactured and sold at a reasonable cost.

The invention proposes a shaft for carrying a propeller and separate from the crank shaft of a motor for driving the propeller, a motor for driving said propeller and having a casing and a crank shaft, means for rotatively supporting the propeller shaft and arranged for communicating all pulling and other stresses to said casing, and means for connecting the propeller shaft and the crank shaft for the transmission of rotations only.

It is conventional to mount the propeller of an aeroplane upon the crank shaft of the driving motor. Some of the most frequent troubles in motors are developed due to the pulling of the propeller upon the crank shaft. No matter how strong the motor may be originally built, the shaft cannot stand the continual pull of the propeller which pull carries the entire aeroplane, and in addition the other stresses due to the rotation of the shaft.

The continuous pull loosens the crank shaft so that it may move slightly longitudinal. When the engine reaches this condition, numerous troubles develop particularly with the operation of the pistons within the cyhnders causing excessive friction and choking of the engine. While the longitudinal movement may be very slight still it is enough to disable the engine. Engines constructed according to this invention obviate this defeet.

For further comprehension of the invention, and of the objects and advantages thereof, reference will be had to the following description and accompanying drawings, and to the appended claims in which the various novel features of the invention are more particularly set forth.

In the accompanying drawings forming a material part of this disclosure Fig. 1 is a fragmentary side elevational yiew of a device constructed according to this invention.

2 is a vertical sectional view 1g. trating a modification.

Fig. 4 is a fragmentary perspective view of acrank shaft constructed for use in the device.

Fig. 5 is a view as though looking in the direction of the line 5-5 of Fig. 2 but illustrating another embodiment.

Fig. 6 is a plan view of the lower half of a crank casing having a crank shaft and a propeller connected therewith according to another embodiment.

Fig. 7 is a view similar to Fig. 6 but illustrating another embodiment.

Fig. 8 is another view similar to Fig. 6 but illustrating a further embodiment.

Fig. 9 is a fragmentary sectional view taken on the line 9-9 of Fig. 7.

Fig. 10 is an enlarged detailed view of a portion of Figs. 6 and 7, showing particularly the mounting in the turn buckles.

Fig. 11 is a sectional view taken on the line 1111 of Fig. 10.

The propeller mounting for aeroplanes and the like consists of a crank casing 10 of a conventional motor having a crank shaft 11. Just one end of this shaft has been illustrated. The crank casing is provided with a detachable section 12. Studs 13 project from the main portion of the crank casing and engage thru apertures in flanges formed on the detachable section, and nuts 14 threadedly engage upon these studs and serve to hold the detachable section in place. A shaft 15 for carrying the pro eller 16 is rotatively mounted in the detacha ble section 12. The rotative mounting is accomplished by thrust bearings 17 spaced from each other and mounted on the detachable section. These thrust bearings should preferably be of the type having adjustable blocks permitting proper alignment.

The end of the crank shaft 11 is shown rotatively supported in bearings 18 mounted within the crank casing. One of these bearings is supported upon a partition 19 and the of Fig. 1.

3 is a View similar to Fig. 2 but illusother upon the end of the casing. A means is and the crank shaft for transmission of rotations only. This means consists of a spur gear 20 on one of the shafts meshing-with a second spur gear 21 on the other. It is pointed out that the propeller shaft 15 after some wear may move slightly longitudinally under the pull of the propeller 16 but such motion will not be transmitted to the crank peller shaft and capable of communicating all pulling and other stresses to the crank casing. In lieu of the spur gear construction for the transmission of rotations only, sprocket wheels and a chain may be used.

In Fig. 3, a modified form of the device has been illustrated in which the detachable section 12 is provided with an intermediate transverse partition 22 and a third thrust bearing 23 is mounted on this partition and coacts with the thrust bearings 17 for the supporting of the propeller shaft. The crank casing 10 is also provided with a partition 24 for supporting an. additional bearing 25 for aiding the bearings 18 in good supporting of the crank shaft 11. A plurality of gears 26 are fixed upon the propeller shaft and mesh with a plurality of gears 27 fixed upon the crank shaft and constitute the means for transmitting rotations. Necessarily all of the gears 26 must be of the same size and this is also true of all of the gears 27.

In Fig. 4, aperspective view of a portion of a crank shaft has been illustrated and is shown provided with a plurality of gears 27. In dot and dash lines 28 the propeller shaft has been schematically shown carrying gears meshingwith the gears 27 A propeller is also shown connected on the shaft. This perspective view it is thought will aid in a better understanding of the disclosure in Fig. 3.

In Fig. 5, another embodiment of the invention has been illustrated in which an arrangement has been shown very similar to the one described in Figs. 1 and 2. It differs that a plate 29 is provided with a dovetailed groove and is slidably mounted upon a stationary dovetailed tongue 30 attached upon the detachable section 12. The bearings 17 are mounted upon this plate instead of directly upon the detachable section as previously recited. A screw 31 is rotatively mounted within the stationary tongue 30 and projects at one end as shown on the drawings. 'This end is formed with a head 32 permitting rotation with a proper tool.

A look nut 33'is shown threadedly engaged upon the screw for locking it in various rotated positions. A lug projects from the plate 29 and threadedly engages the screw 31. This is similar to the showing in Fig. 9.

" A plurality of turn buckles 34 are pivot-ally mounted at one of their ends upon the plate 29 and at their other ends upon eye members 35. These eye members will be fully described further on and the purpose of this construction willbe given in greater detail with specific reference to Figs. 7, 9, 10 and 11.

The propeller mounting for aeroplanes and the like shown in Fig. 6 consists of a shaft 40 for carrying a propeller 41 and separate from the crank shaft 42 of a motor for driving the propeller, a motor for driving said propeller and having a casing 43 housing the said crank shaft 42, means for rotatively supporting the propeller shaft 40 and arranged for communicating all pulling and other stresses to the casing 43, and means for connecting the propeller shaft 40 and the crank shaft 42 for transmission of rotations only.

The shaft 40 extends from the casing 43 and the propeller 41 is mounted upon the extended end. On the drawings only one end of the crank shaft 42 has been illustrated and the remaining portion indicated schematicallyl by dot and dash lines 44. Standards 45 are s own mounted upon thecrank casing 43 and rotatively supporting the end of the crank shaft 42. The propeller shaft 40 is arranged parallel with the crank shaft 42 and is slightly spaced therefrom.

The means for rotatively supporting the propeller shaft and arranged for communicating all pulling and other stresses to the casing consists of a pair of standards 46 mounted upon the casing ards are provided with thrust bearings arranged for rotatively holding the propeller shaft and also holding it against longitudinal movements.

The means for connecting the propeller 1w" shaft and the crank shaft for the transmissions of rotations only, consists of several gears 47 fixed upon the crank shaft 42 and coactable with a group of connected gears 48 unitarily slidably mounted upon the propeller shaft 40. The sliding connection is accomplished by a square portion arranged upon the shaft 40 and engaging in a square aperture formed in the unitarily connected gears 48. These gears may be longitudinally moved by a. control rod 49 having a bent end engaged betweenflanges 50 connected with the group of gears 48.

All pulling from the propeller is transmitted to the thrust bearing 46, and any time when the shaft becomes slightly loose in the bearing and is capable of moving slightly longitudinally, such motion is not communicated to the crank shaft 42 and this materially increases the life of the engine. It will be noticed that the crank shaft is not subject to any longitudinal stresses but merely to rotation. It will at all times remain true and will not cause excessive strains upon the pistons and cylinders of the motor.

In the modified form of the device illustrated in Figs. 7, 9, and 11, an arrangement has been shown very similar to the one just described. It differs in that a base 51 is provided with a bottom dovetail groove 52 and is slidably mounted upon a stationary tongue 53 attached on the crank casing 43. The standards 46 are mounted upon this base instead of directly upon the crank casing as previously recited. A screw 54 is rotatively mounted within the stationary tongue 53 and projects at one end as shown in Fig. 7. This end is formed with a head 55 permitting rotation with a proper tool.

A look nut 56 is shownengaged upon the screw for locking it in various rotated positions. A lug 57 projects from the base 51 and threadedly engages the screw 54. A plurality of turn buckles 58 are pivotally mounted at one of their ends upon the base 51 and at their other ends upon eye members 59. These eye members are slidably mounted on the crank case 43. Each of the eye members is provided with a lateral projection 60 slidably engaged in a slot 61 formed in the crank case 43. The lateral projection 60 is arranged for engaging beneath an overhanging end 62 from the casing and overhanging the slot 61.

, The position of the propeller relative to the outer end of the crank casing may be adjusted by first loosening all of the turn buckles 58 and then adjusting the screw 54 so that the base 51 assumes the desired adjusted position.

Then the turn buckles 58 are manipulated for advancing the eye members 59 so that the lateral projections 60 of each of the members engage beneath the overhanging ends of the slots 61. This securely locks the base in adjusted position. Attention is called that in addition to removing longitudinal stresses from the crank shaft, the propeller shaft itself may be longitudinally adjusted which as is generally known is very advantageous.

In the modified form of the device illustrated in Fig. 8, a propeller shaft 64 is illustrated extending from the crank casing 43. A propeller 41 is mounted upon the extended end of this shaft. The crank shaft is indicated by dot and dash lines 44 and one end of this shaft is shown in full lines and in true alignment with the inner end of the propeller shaft 64. The means for rotatively supporting the propeller shaft 64 consists of a standard 65 mounted upon a base 51. This standard is providedwith a thrust bearing. The base 51' is slidably mounted upon a stationary tongue 53 fixed to the crank casing 43. A screw 54 is rotatively mounted on the tongue 53 and is engaged by a lug from the base 51" in a manner similar to that described relative to Figs. 7 and 9. The base 51 ma be locked in adjusted positions by turn buckles 58. These turn buckles connect with eye members 59 identical to the ones previously described. e

The means for connecting the propeller shaft and the crank shaft for the transmission of rotations only, consists of a disc 66 fixed upon the crank shaft and formed with a plurality of apertures. Another disc 67 is fixed upon the propeller shaft 64 and is provided with a plurality of projecting longitudinal pegs 68 engaged thru the apertures in the disc 66. All rotations from the crank shaft are transmitted to the propeller shaft 64 and the propeller shaft may move slightly longitudinal without transmitting any longitudinal stresses to the crank shaft.

It is to be understood that the separate engine shaft 11 and propeller shafts 15 and 28 will tend to increase the efficiency of the engine, therefore the speed of the engine will lze also increased.

It is also to be understood that the gears on the propeller shaft and crank shafts may be changed to any desired proportion, thereby the number of rotations of the propeller may be changed. In this manner, the speed of the areoplane may be changed.

lVhile I have shown and described the preferred embodiment of my invention, it is to be understood that I do not limit myself to the precise construction herein disclosed and the right is reserved to all changes and modifications coming within the scope of the invention as defined in the appended claims.

Having thus described my invention, what I claim is new, and desire to secure by United States Letters Patent is 1. A propeller mounting for aeroplanes, comprising a shaft for carrying a propeller and separate from the crank shaft of a motor for driving the propeller, a motor for driving'said propeller and having a casing and a crank shaft, means for rotatively supporting the propeller shaft and arranged for communicating all pulling and other stresses to the said casing, means for connecting the propeller shaft and the crank shaft for the transmission of rotations only, and means for adjusting the longitudinal position of the propeller shaft, comprising a base slidably mounted on the crank casing and carrying standards supporting the propeller shaft, means for adjusting the position of the base, turn buckles pivotally connected with the base and with eye members slidably arranged in slots on said crank case.

2. A propeller mounting for aeroplanes, comprising a shaftfor carrying a propeller and separate from the crank shaft of a motor for driving the propeller, a motorfor driving said propeller and having a casing and a crank shaft, means for rotatively supporting the propeller shaft and arranged for comy municating all pulling and other stresses to the said casing, and means for connecting the propeller shaft and the crank shaft for the transmission of rotations only, comprising a disc with apertures fixed upon the crank shaft, a second disc fixed upon the propeller 5 shaft, andpegs projecting from the second disc and engaging thru the apertures in the first disc.

3. A propeller mounting for aeroplanes, comprising a shaft for carrying a propeller and separate from the crank shaft of a motor for driving the propeller, a motor for. driving said propeller and having a casing and a crank shaft, means for rotatively supporting the propeller shaft and arranged for communicating all pulling and other stresses to the said casing, and means for connecting the propeller shaft and the crank shaft for the transmission of rotations only, comprising a disc fixed upon the crank shaft, another disc fixed upon the propeller shaft, said shafts being in line with each other, and pegs proj ecting from one of the discs and engaging in apertures in the other of the discs.

In testimony whereof I have affixed my signature.

SPIROS S. VARKAS. 

